1.A. Field of the Invention
This invention is in the field of methods for milking animals. While the application and the preferred embodiment discuss milking domesticated dairy cattle, the method of this invention is equally suitable for sheep, goats, and other domesticated dairy mammals, and also suitable for other mammalian milking opportunities.
1.B. Description of the Related Art
The days when Heidi milked the family cow have passed. Modern dairy milking is increasingly driven by the need for efficiencies in time and costs, as are almost all present-day agricultural, industrial, and post-industrial processes. Most inventions in this field focused on new equipment (thereby increasing the capitalization required per head). Some focused on improved layouts for the milking facility (the 1990's saw the advent of the ‘carousel’ or ‘roundabout’ milking barn). Further efforts focused on improving and automating the monitoring of the milking; nowadays, the most advanced diaries have at least a milking computer placed in each milking stall, in addition to a central processing and monitoring unit tracking the entire herd's overall condition and milk production.
Getting milk from the udder of a mammal seems straightforward, even an epitome of simplicity. After all, can't every baby mammal manage to do so from the day it is born? But a number of concerns arise when the natural process intended to feed calves is directed (or suborned or hijacked, as PETA might claim) towards hygienic, safe, effective, and reliable production of milk for the marketplace.
Cow udders are normally not sanitary, as they are exposed to the external environment. Contaminating contact can be direct or indirect, e.g. when a hoof brushes the udder or teat when the cow kicks at a fly. Using external antiseptics to sanitize (cleanse and disinfect) the udder and teats greatly improved the hygienic quality of the collected milk, even before it was pasteurized. Today, both udder and teats are sanitized by being swabbed, dipped or sprayed with a germicidal composition, typically iodine-based. This greatly reduces the bacterial spreading both into the milk collected and amongst the cows being milked by the same milking machine.
Most of the germicidal compositions presently in use require a delay or ‘kill time’ between application and the next step, as their manufacturers and the dairymen recognize that these compositions do not provide an ‘instant kill’. This means the method for milking every cow using the prior art must incorporate a 30 to 60 second delay—an interval that adds up when hundreds of cows are being milked. (In fact, if the herd is milked four times a day, or every six hours, at most 360 cows can pass through a single stall each time.)
Prior patents have focused on the compositions, but said little about how such are actually applied. Pallas, et al., U.S. Pat. No. 5,776,479, noted there were two general approaches to providing protection: “using a germicide solution which reduces the number of microbes, or forming a film-forming barrier over the cow's udder which prevents microbes from entering the milk channel;”, but conceded implicitly that neither method was an advance over the prior art, which was stated in that patent's background as including “ . . . teat dips to provide both a continuous barrier film on the cow's teat which persists between milkings and anti-microbial activity . . . ” All Pallas had to say about how any solution was used was, “Typically, the compositions of the invention are applied to the teats, preferably after each milking, by dipping the teat into the liquid composition . . . ” (Similar statements are found in Andrews, Jeffrey F., U.S. Pat. No. 5,063,249, “The teat dip concentrate formulation of Example 1 (i.e., the formulation containing 12.00% of the “Tego 51B”) was applied to all of the teats of four cows in a field trial using normal procedures (i.e., applied twice a day, after each milking) . . . ”; Marhevka; Virginia C., U.S. Pat. No. 5,017,369: “Since dairy farmers are fully accustomed to the use of teat dips, dipping the teats in a cup or other receptacle containing a composition of this invention is the preferred method of applying a coating to the animal's skin . . . ”; Brokken, et al., U.S. Pat. No. 4,945,110, “When applied to the animals' teats and udder quarters . . . ”; Marks, Sr., et al., U.S. Pat. No. 4,434,181 (1984): “a liquid at room temperature in which one can immerse an animal teat to provide a liquid coating that adheres to the animal's teat . . . ”; Silver, J. et al., U.S. Pat. No. 4,199,564 (1980): “There is provided a method for preventing mastitis in the teats of animals comprising applying to the teats that composition and allowing the composition to dry on the teats . . . ”)
Other patentees have presumed an equivalence between the field and the laboratory and never left the latter. (See, e.g. McKinzie, et al. U.S. Pat. No. 5,529,770: “In particular, the four dips were tested to determine their film-forming characteristics. In each case, twenty-five 16 mm diameter glass culture tubes were initially weighed and dipped in the particular teat dip to a depth of 6½ to 7 cm. After dipping, the 25 tubes were allowed to drain for 1 to 1½ minutes and were weighed to provide a wet weight. The tubes were then allowed to dry in ambient air for a period of 45 minutes, whereupon the tubes were reweighed to provide a dry weight.”)
A very recent patent offers little further help. Dyer, D., U.S. Pat. No. 6,525,071, when discussing how the composition which is the focus of that patent is used in the dairy, merely states: “ . . . administering the compositions to mammalian skin, specifically the udder and teats of milking animals . . . ”. That patent did add a bit more detail as to their method of application in an example, where it added the details of: “using a spray-application device . . . compositions applied prior to milking were removed by wiping the teats with a clean disposable towelette before the animal was milked; the antimicrobial compositions applied immediately after the milking were left on the animal and not rinsed off.” But for the most part, the prior art is something ‘applied’ rather than considered.
However once sanitized, the udder and teats then have to be cleaned of this solution, by being either wiped dry or sprayed a second time with water or a neutralizer and then wiped dry. For cleansing and disinfecting solutions based on iodine are caustic; and when applied over days, weeks, and years (literally thousands of exposures), these solutions will chap, burn and harm the teats and udder, if not thoroughly washed off. The person milking the animal is both strongly advised, and prefers, to wear gloves to protect her or his own skin against this solution, despite the decrease in sensitivity and the increase in effort incurred.
Dairy owners, and bovine specialists, have long since established the importance of the ‘let down’ to milking, that is, the relaxation of the teat sphincter muscle which permits the emission of milk when suction is applied to the teat. Stimulation of the teat is a necessary precondition for the let-down to occur, and the proper stimulation can shorten the time interval between attaching a feeder tube from the milking machine to the individual teat and the emission of milk from the udder in response to the vacuum suction in that feeder tube. The existing art focuses on the manual priming of each teat, which means giving each a tug to bring milk down from the udder to the tip of the teat. This manual priming also stimulates the production of oxytocin (the hormone governing milk let-down) within the animal. The better a milking method is at oxytocin stimulation, the sooner and less constricted the milk flows through the teat sphincter. Part of the reason that the delay for the germicidal ‘kill time’ has been ignored in the dairy industry, is that the prior art also incorporated a ‘let down’ delay between the time a teat was primed, and the time the cow was ready to begin milking. But calves rarely are as patient, and the closer the stimulus is to the instinctive expectation, the sooner the milk will flow.
Repetitive tugging at each teat, particularly when combined with a suction effect, stimulates the animal being milked into letting down the milk and empties the udder. Some skill had to be used to reliably deliver the milk to the collection bucket, as Heidi learned. The vacuum-operating milking machine replaced the milkmaid with a tireless and less obtrusive milker, or at least one that didn't require coffee breaks or was at less hazard of hoof imprints. But this still required external intervention, as somebody had to attach an individual feeder tube to each teat.
And so the current method of milking evolved into a seven-step process, which is detailed in FIG. 1 and FIGS. 2, 2A through 2D. Each animal that is to be milked is herded into an individual stall equipped with all the necessary equipment and supplies (some fixed and used for every animal, some variable and disposed with each use). Then the modern Heidi (or Hermann or, in much of the southern and western United States, Hernandos) will: (1) apply a sanitizing solution to the udder (40) and teats (42), typically by dipping using a dipping cup (44) or spraying using a sprayer (46) and spray (48); (2) prime each teat in turn; (3) wipe dry the udder (40) and teats (42) with a (disposable) towel (50) to clear off any remaining and excess sanitizing solution; (4) attach to each teat a feeder tube (54) to the milking machine, whereupon (5) milking takes place. After the cow has been milked, then the milker will (6) remove each feeder tube; and, finally, (7) again spray or dip the udder and teats with a longer-term germicidal and ‘barrier’ solution.
The milker will interact with the dairy animal in each of steps 1, 2, 3, 4, 6, and 7—in other words, in all but step 5. These interactions are marked with an ‘I’ in FIG. 1. Each such interaction is something to which both the milker and the dairy animal must become habituated and, however domesticated the breed may be, at any interaction a particular animal may react antagonistically. Also these interactions can upset, frighten the cow to where she will not release or let down her milk. There is always some risk of the animal reacting to each motion of the laborer, putting an understandable stress on the human who may be kicked, bumped, squeezed against the stall's side, or trampled on. And each step requires both habituation of each animal, and training of each milker, to that step. Since there is continual turnover in the dairy business of both animals and milkers in the barns, this last burden is both real and ongoing.
Separating steps 1&2, 2&3, and 3&4 is an interval during which the cow being milked may kick or react to the motions and sensations of the previous action; and thus, a small chance of contamination (or re-contamination) of the teat from the animal's hoof, leg, or tail, which can adversely affect the milk quality. These delays accommodate for both the ‘kill time’ and some part of the ‘let down’ time mentioned above. Each interval creates a re-contamination risk, and so these are marked with a ‘c’ in FIG. 1. There is also the risk of contamination after the feeder tubes are removed, a risk which may last until the next milking; this is marked with a ‘c*’ in FIG. 1.
The seventh step, post-milking (7), shown in FIG. 1, of spraying again the udder and teats with a different sanitizing and germicidal solution, has become the part of the preferred prior art; this is done in order to reduce mastitis. Because the teat canal can remain open for up to 30 minutes after milking, as it may take that long for the teat-end sphincter muscle to tighten, and because a prime milk cow may be milked as much as four times in 24 hours and will be milked 7 days a week, any sanitizing solution that will remain on the udder or teat should minimize its caustic effect as a secondary goal, reducing its tendency to irritate or damage the skin and mucosal membranes of the teat and teat canal. This is because, while there may be no risk of contaminating the already-collected milk, there is always some risk the teat channel may be contaminated before the next milking while the cow is in the field.
Finally, there is always a pause between steps (4) and (5), a pause which is the function of the gap between the natural and modern processes. Dairy cows originally evolved to suckle their offspring. And despite the miracles of both stock-breeding and genetic engineering, they have not as yet evolved reflexes and stimulus-response patterns most suited to even the best vacuum tubes of milk machinery. This pause between the attachment of the feeder tube and milk let-down may seem insignificant, measuring perhaps seconds per teat per animal—but any pause multiplied by hundreds begins to become noticeable in a 24-hour, 7-day dairy operation where the milking never ceases.
Modern dairies have generally depended upon halide (more specifically, iodine- or chlorine-based) compositions for their sanitizing, pre-milking application. These have generally imposed a noticeable environmental burden on the teats and udders of the dairy cows, the hands of the laborers, and the soils and environs with which they come into contact day after day, month and year after month and year, because of their caustic nature. These solutions also must be cleaned off the teats and udder, preferably before the milking occurs, lest their presence chafe, burn, or stress the teat; crack, weaken, or damage the material(s) of the feeder tube; or degrade the quality of the collected milk where they are not allowed. These unwanted side effects of halide compositions also impose additional material burdens in the form of wiping towels, multiple sprayers and sprays, gloves for the milkers, and even multiple, different germicidal compositions. But the continued low cost and fairly broad microbiocidal spectrum provided by the halide compositions, plus the innate conservatism of even modern dairymen, have led to their continued usage despite their problems and costs.